measures of variability
While measures of central tendency (mean, median, and mode) tell us about the middle or typical values in a data set, measures of variability tell us how spread out the data is.
Why Variability Matters
Imagine two classes took the same math test. Both classes had an average (mean) score of 75%. Does this mean both classes performed exactly the same?
Not necessarily! In one class, most students might have scored between 70-80%, while in the other class, scores might have ranged from 50-100%. The variability or spread of the data tells us this important difference.